134 THREE CRUISES OF THE BLAKE." 
the absence of nectocalyces, whose function is in part taken by 
the covering scales. They are capable of a slight motion on 
their attachment, and by this movement an active propulsion 1s 
produced. The float is large, and 
the stem very much reduced in 
length. The genus is interesting 
from its resemblance to a young 
ERN Dux A 
AP ty <a 3 
a 
Fig. 420, — Gleba hippopus. ?. 
( Fewkes.) 
stage of Agalma having 
no nectocalyces, in which 
a similar circle of covering 
scales 1s found. A new l 
species, A. formosa, from 
the Florida Keys, has been | 
added to the medus:e of 
the Gulf Stream. 
The close resemblance of the swimming-bells of one genus of 
Fig. 425, — Agalma Okenii. |. (Fewkes.) 
the floatless siphonophores to a horse’s hoof suggested the 
name of hippopus to designate a wide-spread Mediterranean 
species (Gleba hippopus, Vig. 429) found in the Gulf Stream 
